High temperature seal for exhaust manifold

ABSTRACT

An exhaust manifold is disclosed. The exhaust manifold includes a plurality of exhaust tubes connected to one another, such that a male connector portion of one exhaust tube is received into a female connector portion of an adjacent exhaust tube. The plurality of exhaust tubes define an exhaust passage therein. The exhaust manifold also includes an air shielding zone surrounding the plurality of exhaust tubes. The exhaust manifold further includes a cooling jacket. The cooling jacket surrounds the air shielding zone. A high temperature seal is disposed within the air shielding zone. The high temperature seal is positioned outside of an interface area of the male and female connector portions of the respective exhaust tubes. The high temperature seal is configured to separate the air shielding zone into regions. Also, the high temperature seal is configured to control fluid communication between the separated regions of the air shielding zone.

TECHNICAL FIELD

The present disclosure relates to an exhaust manifold, and moreparticularly to a high temperature seal for the exhaust manifold.

BACKGROUND

An engine associated with a work machine includes an exhaust manifold.The exhaust manifold is configured to collect exhaust gases from aplurality of cylinders of the engine. In some applications, for examplemarine systems, an exhaust manifold may be formed from a plurality ofindividual exhaust tubes connected to each other. In such an exhaustmanifold, a slip joint is formed at a connection of each of theseindividual exhaust tubes. Cooling is provided to the exhaust manifold bya cooling jacket which encloses an air shielding zone that in turnsurrounds the exhaust tubes. The air shielding zone between the coolingjacket and the exhaust tubes is configured to reduce heat transferbetween a coolant and the exhaust gases passing through the coolingjacket and the exhaust tubes respectively.

U.S. Pat. No. 7,837,233 discloses an exhaust system of an internalcombustion engine includes a slip joint with a female section having anopening with an inner diameter, a male section having an outer diametersmaller than the inner diameter of the opening of the female section,the male section being at least partially received in the femalesection, a wear sleeve disposed between the female section and the malesection, and at least one seal contacting the wear sleeve and at leastone of the female section and the male section, to seal the slip joint.

SUMMARY OF THE DISCLOSURE

In one aspect of the present disclosure, an exhaust manifold isdisclosed. The exhaust manifold includes a plurality of exhaust tubesconnected to one another. The plurality of exhaust tubes are connectedto each other such that a male connector portion of one exhaust tube isreceived into a female connector portion of an adjacent exhaust tube.The plurality of exhaust tubes is configured to define an exhaustpassage therein. The exhaust manifold also includes an air shieldingzone. The air shielding zone surrounds the plurality of exhaust tubes.The exhaust manifold further includes a cooling jacket. The coolingjacket surrounds the air shielding zone. A high temperature seal isdisposed within the air shielding zone. The high temperature seal ispositioned outside of an interface area of the male and female connectorportions of the respective exhaust tubes. The high temperature seal isconfigured to separate the air shielding zone into regions. Also, thehigh temperature seal is configured to control fluid communicationbetween the separated regions of the air shielding zone.

In another aspect of the present disclosure, a method of cooling anexhaust manifold is disclosed. The method includes providing an exhaustpassage. The method also includes providing an air shielding zonesurrounding and in fluid communication with the exhaust passage. Themethod further includes providing a path for coolant flow surroundingthe air shielding zone. The high temperature seal is positioned outsideof an interface area defined between two adjacent exhaust tubes. Themethod includes disposing a high temperature seal in the air shieldingzone. The high temperature seal is configured to separate the airshielding zone into regions. The high temperature seal is furtherconfigured to control fluid communication between the separated regionsof the air shielding zone.

In yet another aspect of the present disclosure, an engine is disclosed.The engine includes a cylinder head. The engine also includes an exhaustmanifold connected to the cylinder head. The exhaust manifold of theengine includes a plurality of exhaust tubes connected to one another.The plurality of exhaust tubes are connected to each other such that amale connector portion of one exhaust tube is received into a femaleconnector portion of an adjacent exhaust tube. The plurality of exhausttubes is configured to define an exhaust passage therein. The exhaustmanifold also includes an air shielding zone surrounding the pluralityof exhaust tubes. The engine further includes a cooling jacketsurrounding the air shielding zone. A high temperature seal is disposedwithin the air shielding zone. The high temperature seal positionedoutside of an interface area of the male and female connector portionsof the respective exhaust tubes. The high temperature seal is configuredto separate the air shielding zone into regions. Also, the hightemperature seal is configured to control fluid communication betweenthe separated regions of the air shielding zone.

Other features and aspects of this disclosure will be apparent from thefollowing description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary engine block including anexhaust manifold, according to one embodiment of the present disclosure;

FIG. 2 is a cross-sectional view of a portion of the exhaust manifoldhaving a high temperature seal installed therein;

FIGS. 3 and 4 are perspective views of the high temperature seal,according to various embodiments of the present disclosure; and

FIG. 5 is a flowchart for a method of cooling the exhaust manifold.

DETAILED DESCRIPTION

Wherever possible the same reference numbers will be used throughout thedrawings to refer to the same or the like parts. FIG. 1 is a perspectiveview of an exemplary engine 100. In one embodiment, the engine 100 mayinclude a compression ignition engine configured to combust a mixture ofair and diesel fuel. In alternative embodiments, the engine 100 mayinclude a spark ignition engine such as a natural gas engine, a gasolineengine, or any multi-cylinder reciprocating internal combustion engineknown in the art. The engine 100 includes an engine block 102. Theengine block 102 includes a plurality of cylinders 104. Each of theplurality of cylinders 104 includes a piston (not shown) and in someembodiments a liner (not shown) disposed within the cylinder 104. Theengine 100 may be provided in association with a variety of applicationssuch as, motor vehicles, work machines, locomotives or marine engines,and in stationary applications for example, electrical power generators.

The engine block 102 also includes a cylinder head 106. The cylinderhead 106 provides intake and exhaust flow communication with thecylinders 104. Further, the engine 100 includes an exhaust manifold 108.The exhaust manifold 108 extends substantially along a longitudinallength of the engine 100. In the present embodiment, the exhaustmanifold 108 is coupled to a plurality of cylinder heads 106 to providefluid communication between an exhaust port associated with thecylinders 104 and an environment surrounding the engine. The engine 100may also include turbochargers 110. In the illustrated embodiment, fourturbochargers 110 are provided at an end of the engine 100. Theturbochargers 110 are configured to increase an efficiency of the engine100. As seen in the accompanying figure, the exhaust manifold 108connects the cylinders 104 to the turbocharger 110, such that exhaustgases flowing out from the cylinders 104 is received by theturbochargers 110.

FIG. 2 is a cross sectional view of the exhaust manifold 108 of theengine 100. The exhaust manifold 108 includes a plurality of exhausttubes. For exemplary purposes, the illustrated embodiment includes threeexhaust tubes 112, 112′ and 112″. The plurality of exhaust tubes 112,112′ and 112″ are connected to one another in an end-to-end manner anddefine an exhaust passage 114 therein. The exhaust tubes 112, 112′ and112″ may have a circular cross section. Further, each of the exhausttubes 112, 112′ and 112″ includes a male connector portion 115. As shownin the accompanying figures, one end of the exhaust tubes 112, 112′ and112″ includes a stepped portion 116, such that the end of the exhausttubes 112, 112′ and 112″ has an increased diameter. The stepped portion116 defines a female connector portion 117 on each of the exhaust tubes112, 112′ and 112″. The stepped portion 116 of the exhaust tubes 112,112′ and 112″ is configured to receive the male connector portion 115 ofthe corresponding exhaust tubes 112, 112′ and 112″. Further, theconnection of the two exhausts tubes forms a slip joint 118therebetween.

During an operation of the engine 100, an outer surface of the exhaustmanifold 108 may become hot due to the passage of the exhaust gasestherewithin. The exhaust manifold 108 may be surrounded by a coolingjacket 120 in order to control the temperature of the outer surface ofthe exhaust manifold 108. The cooling jacket 120 may include a coolant,flowing therethrough. The coolant may be pumped from a pump (not shown)associated with the engine 100 for distribution of coolant in thesystem. The cooling jacket 120 may be embodied as a shell having aninner wall 122 and an outer wall 124 spaced from each other, betweenwhich the coolant may flow. It should be noted that a diameter of theinner wall 122 of the cooling jacket 120 is greater compared to adiameter of the plurality of exhaust tubes 112, 112′ and 112″, such thata gap is provided therebetween. The gap defines an air shielding zone126, wherein the air shielding zone 126 is positioned between theexhaust tubes 112, 112′ and 112″ and the cooling jacket 120. The airshielding zone 126 contains air therein and is configured to reduce heattransfer between the coolant and the exhaust gases flowing through thecooling jacket 120 and the exhaust tubes 112, 112′ and 112″respectively.

During operation of the engine 100, the exhaust gases may flow throughthe exhaust tubes 112, 112′ and 112″ at a high velocity. This exhaustgas may also be at a high temperature due to combustion processes in theengine 100. A portion of the exhaust gases may leak out or pass throughthe slip joints 118 or any other openings present within the exhausttubes 112, 112′ and 112″ and enter into the air shielding zone 126, theair shielding zone 126 being at a comparatively lower pressure. This maycause an overall increase in temperature of the air shielding zone 126due to the passage of the exhaust gases therethrough. The passage of theexhaust gases may also affect an efficiency of the cooling systemassociated with the cooling jacket 120. Further, overall systemperformance and efficiency of a turbocharger 110 may also be impacted.

In the present disclosure, a high temperature seal 128 is disposedwithin the air shielding zone 126. The exhaust gases flowing through theexhaust manifold 108 may be at a temperature above 750° Celsius. Thehigh temperature seal 128 is exposed to such high temperature exhaustgases. Accordingly, the high temperature seal 128 may be made of a metalwhich may have high resistance to heat. In one example, the hightemperature seal 128 may include a stainless steel mesh. The stainlesssteel mesh may further include fiber glass cloth and silica/fiberglassinsulation.

As shown in the accompanying figures, the high temperature seal 128 isdisposed proximate to the slip joint 118 of the exhaust tubes 112, 112′and 112″. The high temperature seal 128 of the present disclosure isconfigured to separate the air shielding zone 126 into regions 130.Further, the high temperature seal 128 is configured to control fluidcommunication between each of the separated regions 130 so formed.Accordingly, the high temperature seal 128 is configured to minimizeand/or prevent the exhaust gases that may have leaked into the regionsof the air shielding zone 126 through the respective slip joints 118from communicating with each other. The high temperature seal 128 mayserve as a barrier within the air shielding zone 126 and may hence serveas an obstruction in the path of the exhaust gas that may have leakedinto the air shielding zone 126 from freely flowing between the adjacentregions 130 so formed. Accordingly, the exhaust gases flowing withineach of the separated regions 130 may have a reduced velocity.

Further, the high temperature seals 128 may be positioned at differentlocations within the system. For example, a number of high temperatureseals 128 may be positioned at each of the slip joints 118. In anotherexample, the high temperature seals 128 may be positioned at everyalternate slip joint 118 present in the system.

FIGS. 3 and 4 are perspective views of different configurations of thehigh temperature seal 128, according to various embodiments of thepresent disclosure. The high temperature seal 128 has a ring likestructure. The high temperature seal 128 is installed within the systemin such a manner that an inner diameter d1 of the high temperature seal128 contacts with the outer surface of the exhaust tubes 112, 112′ and112″ and an outer diameter d2 of the high temperature seal 128 contactswith the inner wall 122 of the cooling jacket 120. Attachment betweenthe high temperature seal 128 and the exhaust tubes 112, 112′ and 112″aswell as the cooling jacket 120 respectively may be accomplished in avariety of ways. In one example, the high temperature seal 128 may beattached by welding. Alternatively, any other known method may beutilized.

The high temperature seal 128 is positioned within the air shieldingzone 126 in such a manner that a clearance may be present between theslip joint 118 of the exhaust tubes 112, 112′ and 112″and the hightemperature seal 128. During operation of the engine 100, the exhaustgases passing through the slip joint 118 may be re-directed by the hightemperature seal 128 to flow in a direction opposite to a direction offlow of the exhaust gases within the exhaust tubes 112, 112′ and 112″(see arrows in FIG. 2). Referring to FIG. 3, a flange 132 may extendfrom the high temperature seal 128, such that the flange 132 defines anangular side surface extending from the exhaust tubes 112, 112′ and112″towards the cooling jacket 120. When installed, as shown in FIG. 2,a periphery 134 of the flange 132 may contact with the inner wall 122 ofthe cooling jacket 120.

In an alternate embodiment, as illustrated in FIG. 4, the hightemperature seal 128 may have a ring shape. When installed, the innerdiameter d1 of the high temperature seal 128 is configured to contactwith the outer surface of the exhaust tubes 112, 112′ and 112″, and theouter diameter d2 is configured to contact with the inner wall 122 ofthe cooling jacket 120. In this embodiment, a cross sectional area ofthe high temperature seal 128 is equal to a thickness of the airshielding zone 126 in order to control the fluid communication betweenthe regions 130 of the air shielding zone 126. The high temperature seal128 may be embodied as a bulb seal. The design and shape of the hightemperature seals 128 disclosed herein are exemplary and do not limitthe scope of the present disclosure.

INDUSTRIAL APPLICABILITY

The high temperature seal 128 disclosed herein is provided within theair shielding zone 126, and more particularly proximate to the slipjoint 118 of the exhaust tubes 112, 112′ and 112″. The air shieldingzone 126 is relatively easier to access for installation purposes of thehigh temperature seal 128. The high temperature seal 128 provides adurable solution having a reduced cost.

By the separation of the air shielding zone 126 into the regions 130,the high temperature seal 128 is configured to isolate the adjacentregions 130 from one another and minimize or prevent the exhaust gasesfrom flowing therethrough. The high temperature seal 128 is configuredto reduce an overall speed of the exhaust gases flowing through the airshielding zone 126 and thereby decrease heat transfer between theexhaust gases and the coolant. This may prevent the increase in theoverall temperature of the air shielding zone 126. As a result, coolingefficiency provided by the cooling jacket 120 may be increased.

FIG. 5 is a flowchart for a method 500 of cooling the exhaust manifold108. At step 502, the exhaust passage 114 is provided. At step 504, theair shielding zone 126 is provided in the exhaust manifold 108. At step506, a path for the coolant flow is provided surrounding the airshielding zone 126. As described above, the path is defined by thecooling jacket 120 that includes the inner and outer walls 122, 124.

At step 508, the high temperature seal 128 is disposed in the airshielding zone 126. More particularly, the high temperature seal 128 ispositioned outside of an interface area defined between two adjacentexhaust tubes 112, 112′ and 112″. At step 510, the high temperature seal128 is configured to separate the air shielding zone 126 into theregions 130. At step 512, the high temperature seal 128 is configured tocontrol the fluid communication between the separated regions 130 of theair shielding zone 126. In one embodiment, the high temperature seal 128may be welded within the air shielding zone 126.

While aspects of the present disclosure have been particularly shown anddescribed with reference to the embodiments above, it will be understoodby those skilled in the art that various additional embodiments may becontemplated by the modification of the disclosed machines, systems andmethods without departing from the spirit and scope of what isdisclosed. Such embodiments should be understood to fall within thescope of the present disclosure as determined based upon the claims andany equivalents thereof

What is claimed is:
 1. An exhaust manifold comprising: a plurality ofexhaust tubes connected to one another such that a male connectorportion of one exhaust tube is received into a female connector portionof an adjacent exhaust tube, the plurality of exhaust tubes configuredto define an exhaust passage therein; an air shielding zone surroundingthe plurality of exhaust tubes; a cooling jacket surrounding the airshielding zone; and a high temperature seal disposed within the airshielding zone, the high temperature seal positioned outside of aninterface area of the male and female connector portions of therespective exhaust tubes, the high temperature seal configured toseparate the air shielding zone into regions and control fluidcommunication between the separated regions of the air shielding zone.2. The exhaust manifold of claim 1, wherein the high temperature seal ispositioned within the air shielding zone such that the high temperatureseal is in contact with an inner wall of the cooling jacket and an outersurface of the exhaust tube.
 3. The exhaust manifold of claim 2, whereinthe high temperature seal has a ring-like shape, having an innerdiameter configured to contact with the outer surface of the exhausttube and an outer diameter configured to contact with the inner wall ofthe cooling jacket.
 4. The exhaust manifold of claim 2, wherein the hightemperature seal includes a flange extending angularly from a peripheryof the high temperature seal, the flange configured to contact with theinner wall of the cooling jacket.
 5. The exhaust manifold of claim 1,wherein the high temperature seal is positioned within the air shieldingzone in such a manner that a clearance is present between a slip jointof two connected exhaust tubes and the high temperature seal.
 6. Theexhaust manifold of claim 1, wherein the high temperature seal is madeof stainless steel.
 7. A method of cooling an exhaust manifold, themethod comprising: providing an exhaust passage; providing an airshielding zone surrounding and in fluid communication with the exhaustpassage; providing a path for coolant flow surrounding the air shieldingzone; and disposing a high temperature seal in the air shielding zone,the high temperature seal positioned outside of an interface areadefined between two adjacent exhaust tubes, wherein the high temperatureseal is configured to: separate the air shielding zone into regions; andcontrol fluid communication between the separated regions of the airshielding zone.
 8. The method of claim 7, wherein disposing the hightemperature seal further includes welding the high temperature sealwithin the air shielding zone.
 9. The method of claim 7 furthercomprising: directing, by the high temperature seal, at least a portionof an exhaust gas passing through a slip joint in a direction opposing adirection of flow of the exhaust gas within the exhaust passage.
 10. Anengine comprising: a cylinder head; and an exhaust manifold connected tothe cylinder head, the exhaust manifold comprising: a plurality ofexhaust tubes connected to one another such that a male connectorportion of one exhaust tube is received into a female connector portionof an adjacent exhaust tube, the plurality of exhaust tubes configuredto define an exhaust passage therein; an air shielding zone surroundingthe plurality of exhaust tubes; a cooling jacket surrounding the airshielding zone; and a high temperature seal disposed within the airshielding zone, the high temperature seal positioned outside of aninterface area of the male and female connector portions of therespective exhaust tubes, the high temperature seal configured toseparate the air shielding zone into regions and control fluidcommunication between the separated regions of the air shielding zone.11. The engine of claim 10, wherein the high temperature seal ispositioned within the air shielding zone such that the high temperatureseal is in contact with an inner wall of the cooling jacket and an outersurface of the exhaust tube.
 12. The engine of claim 11, wherein thehigh temperature seal has a ring-like shape, having an inner diameterconfigured to contact with the outer surface of the exhaust tube and anouter diameter configured to contact with the inner wall of the coolingjacket.
 13. The engine of claim 11, wherein the high temperature sealincludes a flange extending angularly from a periphery of the hightemperature seal, the flange configured to contact with the inner wallof the cooling jacket.
 14. The engine of claim 10, wherein the hightemperature seal is positioned within the air shielding zone in such amanner that a clearance is present between a slip joint of two connectedexhaust tubes and the high temperature seal.
 15. The engine of claim 11,wherein the high temperature seal is made of stainless steel.